Source code for matx.vision.posterize_op

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from typing import Any, List
from .constants._sync_mode import ASYNC
import random
from ..native import make_native_object

import sys
matx = sys.modules['matx']


class _PosterizeOpImpl:
    """ PosterizeOp Impl """

    def __init__(self,
                 device: Any,
                 bit: int = 4,
                 prob: float = 1.1) -> None:
        self.op: matx.NativeObject = make_native_object(
            "VisionPosterizeGeneralOp", device())
        self.prob: float = prob
        self.bit: int = bit

    def __call__(self,
                 images: List[matx.runtime.NDArray],
                 bits: List[int] = [],
                 sync: int = ASYNC) -> List[matx.runtime.NDArray]:
        batch_size: int = len(images)
        if len(bits) != 0 and len(bits) != batch_size:
            assert False, "The length of bits should be equal to input images"
        if len(bits) == 0:
            bits = [self.bit for _ in range(batch_size)]
        if self.prob >= 1.0:
            return self.op.process(images, bits, sync)
        for i in range(batch_size):
            if random.random() >= self.prob:
                bits[i] = 8
        return self.op.process(images, bits, sync)


[docs]class PosterizeOp: """ Apply posterization on images. i.e. remove certain bits for each pixel value, e.g. with bit=4, pixel 77 would become 64 (the last 4 bits are set to 0). """
[docs] def __init__(self, device: Any, bit: int = 4, prob: float = 1.1) -> None: """ Initialize PosterizeOp Args: device (Any) : the matx device used for the operation bit (int, optional): bit for posterization for all images, range from [0, 8], set to 4 by default. prob (float, optional): probability for posterization on each image. Apply on all by default. """ self.op_impl: _PosterizeOpImpl = matx.script(_PosterizeOpImpl)(device=device, bit=bit, prob=prob)
[docs] def __call__(self, images: List[matx.runtime.NDArray], bits: List[int] = [], sync: int = ASYNC) -> List[matx.runtime.NDArray]: """ Apply posterization on images. Only support uint8 images Args: images (List[matx.runtime.NDArray]): target images. bits (List[int]): posterization bit for each image. If not given, the bit for op initialization would be used. sync (int, optional): sync mode after calculating the output. when device is cpu, the params makes no difference. ASYNC -- If device is GPU, the whole calculation process is asynchronous. SYNC -- If device is GPU, the whole calculation will be blocked until this operation is finished. SYNC_CPU -- If device is GPU, the whole calculation will be blocked until this operation is finished, and the corresponding CPU array would be created and returned. Defaults to ASYNC. Example: >>> import cv2 >>> import matx >>> from matx.vision import PosterizeOp >>> # Get origin_image.jpeg from https://github.com/bytedance/matxscript/tree/main/test/data/origin_image.jpeg >>> image = cv2.imread("./origin_image.jpeg") >>> device_id = 0 >>> device_str = "gpu:{}".format(device_id) >>> device = matx.Device(device_str) >>> # Create a list of ndarrays for batch images >>> batch_size = 3 >>> nds = [matx.array.from_numpy(image, device_str) for _ in range(batch_size)] >>> bits = [1, 4, 7] >>> op = PosterizeOp(device) >>> ret = op(nds, bits) """ return self.op_impl(images, bits, sync)